In an existing mobile communications system, because of mobility of a user equipment (UE) and complexity and variety of radio channel quality, the UE needs to start a measurement operation on a serving cell, a neighboring cell, a frequency, or the like, according to a configuration of a radio network controller on a network side. If a measurement result meets a specific condition, a cell selection or reselection operation of the UE or a redirection, handover, or cell change operation of the radio network controller can be performed so that the UE camps on a most proper cell.
For example, in a universal mobile telecommunications (UMTS) system, when the UE is in a cell forward access channel (CELL_FACH) state, the UE can start measurement according to configuration parameters in a system broadcast message and select a proper cell by using a cell reselection manner. Meanwhile, on the network side, the radio network controller can hand over, according to a load situation of a current cell or a service type of the UE and by means of a redirection or cell change operation, the UE to a target cell or frequency specified by the radio network controller. However, when the radio network controller specifies a target frequency or cell during the redirection, handover, or cell change operation, the radio network controller cannot reference real-time signal quality of the UE. Therefore, when the UE executes a corresponding operation according to an instruction of the radio network controller, if signal quality of the target cell or the target frequency is poor, the redirection, handover, or cell change operation fails.
When the UE is in a cell dedicated channel (CELL_DCH) state, the UE does not execute cell reselection, and the radio network controller can instruct, by using a UE-specific message, for example, a measurement control (MC) message, the UE to perform measurement. If the measurement result meets a specific condition, the UE can report a measurement result to the radio network controller by using a measurement report (MR) message, to assist the radio network controller in executing the redirection, handover, or cell change operation. When the radio network controller makes a redirection, handover, or cell change decision, the radio network controller can reference the signal quality of the target cell or frequency reported by the UE. Therefore, when the UE executes a related operation according to the instruction of the radio network controller, an operation failure probability due to poor signal quality of the target cell or frequency can be reduced.
Generally, the MC message may include one or more pieces of information such as a measurement identity (ID), a measurement command (e.g. establish, modify, or release command), measurement report reporting manner, an additional measurement list, and a measurement type.
The measurement type generally may include one or more pieces of information such as a measurement object, a measurement quantity, a reporting quantity, a measurement reporting criterion, and measurement validity.
The radio network controller may indicate a specific measurement type in the measurement object, for example, an intra-frequency measurement, an inter-frequency measurement, an inter-system measurement, and a position measurement. The intra-frequency measurement refers to a measurement on a cell that is in a same system as a serving cell of the UE and has a same frequency as the serving cell of the UE. The inter-frequency measurement refers to a measurement on a cell that is in a same system as a serving cell of the UE but has a frequency different from that of the serving cell of the UE, as well as on the frequencies. The inter-system measurement refers to a measurement on a system that is different from a system to which a serving cell of the UE belongs. The UE can execute different measurements on different systems. For example, for a global system for mobile communications (GSM) system, the UE may execute measurement on a cell and a frequency; and for a long term evolution (LTE) system, may execute measurement only on a frequency. In addition, the radio network controller may further indicate a cell or a frequency to be added to or deleted in a measurement object. The UE can execute an adding or deletion operation on cells or frequencies in a cell information list (CELL_INFO_LIST) or an evolved universal terrestrial radio access (EUTRA) frequency information list (EUTRA_FREQUENCY_INFO_LIST) stored on the UE. Optionally, the radio network controller may carry a list of a cell to be measured or a frequency to be measured in the measurement object to further specify cells or frequencies that need to be measured by the UE. If the measurement object does not carry the list of the cell to be measured or the frequency to be measured, the UE needs to perform measurement on all cells and/or frequencies in the cell information list and/or the frequency information list. The measurement reporting criterion defines a reporting mode, that is, periodical reporting or event-triggered reporting. Periodical reporting indicates that the UE reports a measurement result to the radio network controller at an interval of a specific time. Event-triggered reporting means that the radio network controller first defines a series of events and the UE reports a measurement result to the radio network controller only when these events are met. The series of events may include, for example, events that signal quality of a serving cell is higher than a threshold, signal quality of a serving cell is lower than a threshold, average signal quality of a target cell within a period of time is higher than a threshold, and the like.
When requiring the UE to execute a report measurement, the radio network controller can set the foregoing information properly in the MC message, so that the UE is capable of executing a report measurement and reporting a measurement result.
In addition, the MR message may generally include one or more pieces of information such as a measurement ID, a measurement result, and an event result.
The foregoing prior art of executing a report measurement has the following disadvantages: 1. A report measurement solution based on an MC message and an MR message can be used only when the UE is in a CELL_DCH state; 2. When the UE is in the CELL_FACH state, because the UE needs to execute cell reselection measurement, if the solution used when the UE is in the CELL_DCH state is directly introduced, the cell reselection measurement may be affected.
In the existing mobile communications system, the following manner used to report a measurement result is provided.
A radio network controller may broadcast, by using a system information block (SIB) message, a report indication to a UE in the system. Generally, the report indication may include an intra-frequency measurement indication and/or an inter-frequency measurement indication. The intra-frequency measurement indication may include a reporting quantity (for example, a ratio of energy per chip to noise spectral density Ec/N0, and reference signal received power RSRP) and the number of reported cells that are reported during the intra-frequency measurement. The inter-frequency measurement indication may include a reporting quantity (for example, Ec/N0 and RSRP), the number of reported cells, a reporting threshold, and the like that are reported during the inter-measurement.
After the UE executes a measurement, the UE can send a measurement result to the radio network controller by using an uplink signaling message. For example, the UE can generate, based on the measurement result, a measurement information element, for example, a measurement information element of measurement results on a random access channel (RACH) (Measured Results on RACH), and use an uplink signaling message such as an RRC connection request message (on a common control channel CCCH), a cell update message (on the CCCH), an initial direct transfer message (on a dedicated control channel DCCH), and an uplink direct transfer message (on the DCCH) to carry the measurement information element, so that signal quality of intra-frequency and/or inter-frequency cells measured by the UE is carried to the radio network controller.
However, because an uplink signaling message on the CCCH, for example, the RRC connection request message and the cell update message, has the fixed maximum number of uplink transmission bits (for example, for an R99 channel, the maximum number of uplink transmission bits is a fixed value; for an eRACH channel, the maximum number of uplink transmission bits depends on an initial authorized value), the following regulations are generally used: 1. The UE reports only valid measurement results to the radio network controller; 2. If a remaining size of the uplink signaling message on the CCCH cannot meet a requirement for reporting the measurement information element, the UE does not perform reporting; otherwise, the UE reports intra-frequency measurement results or measurement results of both the intra-frequency measurement and the inter-frequency measurement according to a specific situation, that is, it reports the intra-frequency measurement results preferentially.
Generally, the reported measurement results include the intra-frequency measurement results and/or the measurement results of the inter-frequency measurement. In the intra-frequency measurement results, the signal quality of the serving cell needs to be included, but signal quality of another cell to be measured is optional, and the signal quality of another cell to be measured may be reported according to the best signal quality. A measurement result of the inter-frequency measurement generally includes an ID of a cell with signal quality reaching a threshold, measurement values (specific to SIB 11 or SIB 12) of the cell, and the like. If the uplink signaling message on the CCCH is used for reporting and a size of the uplink signaling message is limited, the number of cells in the reported measurement result should be limited, and the number of cells in the measurement result of the inter-frequency measurement should be limited preferentially.
The foregoing prior art of executing a report measurement has the following disadvantages: 1. The prior art is applicable to intra-frequency measurement and inter-frequency measurement only; 2. The report indication can only indicate a cell to be measured; 3. A precedence order for reporting measurement results are not specified for inter-system measurement.
Therefore, this field requires a technology that can more efficiently implement a report measurement and reporting of a measurement result.